EXHIBITS: Mapping an Asian Biodiversity Hot Spot

South-central China and eastern Tibet shelter more plant species than almost any place on Earth, including a beautiful Osbeckia crinita flower. Between 1924 and 1927, the American botanist and explorer Joseph Rock (1884-1962) trekked through the area and nabbed specimens of more than 20,000 plants and 1000 birds. This site from Harvard's Arnold Arboretum is a portal to the university's trove of documents and photos about Rock's expedition.

You can track Rock's progress on his hand-drawn maps, browse a selection of his letters, and read published papers by him and others describing the specimen haul. A search feature lets you summon hundreds of original black-and-white photos from the expedition that capture the area's spectacular gorges and vegetation. A linked site describes recent Arboretum expeditions to the plant-rich region, which is threatened by deforestation and erosion.

DATABASE: All Eyes on the Father of Chemistry

The French chemist Antoine Laurent Lavoisier helped establish modern chemical nomenclature, named oxygen and discovered its role in combustion, and propounded the law of conservation of matter—achievements that inspire textbooks to dub him the father of modern chemistry. The Panopticon Lavoisier, a collection of documents and images sponsored by institutions in Paris and Florence, lets you explore the contributions of this lawyer-turned-scientist.

The detailed chronology follows his life from his birth in 1743 to his beheading in 1794 during the French Revolution. Visitors who know French can read his six-volume collected works, scanned from original texts. The site also features a gallery of Lavoisier's instruments, from balances and barometers to calorimeters for gauging the heat output of reactions.

MEETINGS: SARS Takes Center Stage

If only every scientific meeting had a Web archive like this. Almost 100 experts packed the tiny auditorium of the New York Academy of Sciences in Manhattan on 17 May to discuss severe acute respiratory syndrome (SARS): how the virus operates, its impact in China and Toronto, and how drugs and vaccines might stop it. Now, the academy and Columbia University have turned the gathering into a simple, friendly site that raises the bar on online meeting coverage. Watch crisp video of every talk, divided into chapters, while you click your way through the original slide show. Or if you're in a hurry, scan the transcripts or outlines of the presentations. Registration is free.

EDUCATION: Speaking of Science

Entomologist May Berenbaum of the University of Illinois, Urbana-Champaign, admits that as a child she was terrified of insects. While astrophysicist Richard McCray of the University of Colorado, Boulder, was working with Soviet scientists during the Cold War, he had to face another kind of chilly atmosphere: a Moscow winter in an empty, unheated office building. Those are two personal highlights from this set of audio interviews with members of the National Academy of Sciences. During the hourlong chats recorded last year, eight academy scientists discuss their backgrounds, interests, inspirations, and concerns. Check back later this year for interviews with another eight scientists.

LINKS: Location, Location, Location

Everything from the murder rate to plant productivity varies geographically. Researchers seeking such spatially linked data for the United States, in fields from public health to geology, should steer to this guide from the University of Arkansas, Fayetteville. The collection of links tallies hundreds of maps and Geographical Information Systems data sets held by federal, state, and local agencies. Examples include regional birth and death statistics for Alaska, changes in land cover along the shores of the Great Lakes between 1996 and 2001, and this Environmental Protection Agency map of streams damaged or threatened by pollution in Washington state. Most of the data sets and maps are free and accessible online.